February 1999

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Features

Reaching for the Stars

By Stephanie D. Leifer

Light Sails

By Henry M. Harris

Highways of Light

By Leik N. Myrabo

High Blood Pressure and the Slave Trade

Compact Nuclear Rockets

By James R. Powell

Air-Breathing Engines

By Charles R. McClinton

The Puzzle of Hypertension in African-Americans

Genes are often invoked to account for why high blood pressure is so common among African-Americans. Yet the rates are low in Africans. This discrepancy demonstrates how genes and the environment interact

By Richard S. Cooper, Charles N. Rotimi and Ryk Ward

Supersoft X-ray Stars and Supernovae

Several years ago astronomers came across a new type of star that spews out unusually low energy x-rays. These so-called supersoft sources are now thought to be white dwarf stars that cannibalize their stellar companions and then, in many cases, explode

By Peter Kahabka, Edward P. J. van den Heuvel and Saul A. Rappaport

How Limbs Develop

A protein playfully named Sonic hedgehog is one of the long-sought factors that dictate the pattern of limb development

By Robert D. Riddle and Clifford J. Tabin

Departments

Space Tethers

The Way to Go in Space

Not Cleaning Up

Cichlids of the Rift Lakes

A Multifractal Walk down Wall Street

From the Editor

Worm Gets the Early Bird

Letters

Letters

Erratum

Recommended

Reviews: The Narrative of Numbers

Reviews: The Narrative of Numbers

Anti Gravity

This is only a Test

50, 100 & 150 Years Ago

50, 100 and 150 Years Ago: Research Money, Panama Canal, and New Whaling Ground

Wonders

Noah's Flood?

Profile

Bones to Pick

Mathematical Recreation

Origami Tessellations

Amateur Scientist

Tackling the Triple Point

Science and the Citizen

Taming Maxwell's Demon

Attack of the Fire Ants

By the Numbers

Tranquility, Turmoil and Chaos for International Business

Working Knowledge

Working Knowledge on Giant Crawler Cranes

Cyber View

Private Parts

Technology and Business

A Laser in Tune With Itself

Breath of Fresh Liquid

Purchase To Read More

Digital Issue ?Read or download this issue’s articles online. *A printed copy of this issue is not included. $7.99

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